Variocoupler



JanVZO. 1925. I 1,523,464

' c. o. TUSKA VARIOCOUPLBR Filed June 17, 1922 3 Sheets-Sheet l ATTORNEYS CZ. D. TUSKA VARIOCOUPLER Filed June 17,. 1922 3 Sheets-Sheet 2 H AP WM Vww if z 1 &\

INVENTOR M if BY W M ATTORNEYS Jan. 5 i 1,523,464

c. D. TUSKA VARIOCOUPLER Filed June 17,1922 3 Sheets-Sheet 3 INVENTOR Q BY ATTORNEYS Patented Jan. Ell, i925.

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nil in \i as CLARENCE I). TUSKA, OF HARTFORD. CONNECTICUT.

VARIOCGUILEB.

Application filed June 17,

To (17/ IF/l/JNL it may concern:

lie it known that. l. munncn D. 'lUsKA,

a citizen ot' the United States. residing atllartford, in the county of l-larttord: and State ot (onueclicut have invented new and useful lmprovements in l ariocouplt-zrs, of which the following is a specification.

The present invention has reference to vario-couplcrs, vario-ineters and the like such as are used for varying the inductive relation between coils of radio circuits.

One object of the invention is to provide certain new and useful improvements in such devices tending to simplify their construction, to facilitate the assembly of their parts, and to otherwise adapt, the apparatus for economical quantity production.

With these and other objects in view. as will appear from the following specification, the invention resides in the features of construct-ion and in the combinations and arohvious to those skilled 1n the art.

rangerncnts of parts-hereinafter described and claimed. the advantap'es of which will he ln the particular embodiment shown in the drawings the invention is shown as applied to a vario-coupler.

In the drawings:

Fig. 1 is a plan view of a vario-coupler constructed in accordance with the present invention Fig. 2 is a sectional view taken along: the line 22 of l ig. 1;

Fig. 3 is a. view. in end elci-"ation oi a portion of the vario-cmipler;

Fig. 4 is a plan view ot "a portion of the stationary tuhular t'ranie for suppmting;- the primary winding; I

5 is a fragmentary plan view of the rotor shell which supports the secondary winding;

Fig. 6 is a detail view. in perspective. or a portion oi i supporting panel showingone of the lugs upon which the coupler is mounted; and

Fig. '7 is a view, in central vertical, section. showing a modification of the coupler illustrated in Fi 1 and 2.

Referring to r l and 2 of the drawings the primary or stationary winding of the coupler is shown at l and the secondary or movahle winding at 2. The primary winding 1 is wound upon a stator or tuhular supporting frame 3 and is provided with the usual taps & (Fig. 1) leading to the con- 1922. Serial No. 569.084.

such as is s. J. i 1 c generall employed LG \arv the numoer OI tacts ot' a multipoint switch active turns in the winding. The movable arm of the switch 5 is adapted to he connectcd by means ot a conductor 6 with one side oi the antenna circuit while the primary winding is adapted to he connected through suitable conductors (not shown} with the ground.

The secondary winding a is carried by a rotor 10 comprising an annular frame hav-' ing a spherical exterior surface to receive the winding. The rotor frame is constructed of molded dielectric material and is pro vidcd with diametrically disposed trunnions l2 and 13 which have their inner ends molded in the rotor frame and thus securely anchored therein. The rotor trunnions 12 and 13 extend at right angles to the axis of the stator shell 3 and are journaled in l earing sleeves l4- and 15 carried by and electrically connected with conductors 1t) and 17. the latter heinp; in the form of fiat metal straps which are rigidly secured to the stator frame. Thus. the conductor straps l5 and l6. in addition to conducting the current. serve also to maintain the stator and rotor in assembled relation. The

stator frame is rigidly secured to the panel 12 hv means of screws 19 and 19 which ex- 8 tend through the coi'iductor strap 16 and which may he ren'ioved to permit the detael'izncnt ot the coupler from the panel. When the coupler is thus detached from the supporting; panel the rotor and stator will remain in asscmhlcd relation and may be handled as a unit. as will hereina' r appear.

The stator shell 3 is molded with an enlargement 20 at one end providing an annular shoulder 2! which Functions to engage the outermost turn at the respective end ot the primary winding to retain the san'ieagrainst displacement. At the opposite end 0? the stator shell. and at diametrically o iosite ioints in the ahuttahle. ed e face l of said end are located two semi-circular notches one oi which is shown clearly at 22 in Fig.4. and these notches are adapted to receive the hearing sleeves l t and if? to locate the latter with respect to the stator shell and to assist in inaintaining 'the conductor straps l7 and ill in place. y

The conductor strap 'lti carri 's the hearing sleeve suhstantially midway etwecn its ends. [it one side of the hearing 1% the strap 16 lies in engagement with the inner peripheral face of the stator shell and extends to the shouldered end of the shell, where it is apertured to receive the screw 1& The screiv 18 extends through the strap 16 and through the stator shell and is threaded into a lug 23 that is molded upon the panel 12.

The lug 23 has an arcuate face 24 (Fig. 6) shaped to fit the curve of the stator shell for a substantial distance at either side of the fastening screw 18 to insure that the shell .will be rigidly supported. At theopposite side of the bearing 14, the strap 16 extends to a point above a lug 25 on the panel 12 to which lug {the strap is rigidly secured by means of the screw 19 which extends through a slot 26 in the strap 16. The lug 25 isa duplicate of the lug 23, having a similar arcuate face whichis adapted to function as a support for an extension or duplicate of the stator shell which may be assembled with the'apparatus if desired as will later appear. In the absence or" such a stator extension, the conductor strap 16 is fastened by the screw 19 directly to the arcuate face of the lug 25, as shown in toning bolts were employed to hold 2, the strapbeing slightly offset, as shown at 27 to bring its extremity into the plane of the adjacentrhce of the lug 25. In the assembling of the parts, should the offset 27 of strap 18 be such that the axis 12 of the rotor is notv perpendicular to the panel 12, a readjustment to bring this about is made possible by simply bending the free end or said strap 16 in the proper direction and securing the same in position by the screw 19. strap 16 will readily; accommodate any such adjustments in the positioning of said strap. A wire 28 which is clamped between the head of the screw 19 and the strap 27 leads to one side of the receiving circuit.

The conductor strap l'lcarries at one end the bearing sleeve 15 -which is adapted to fit within one of the notches 22 in the stator shell. The strap 17 extends along the inner surface of the stator shell to the thickened end of the latter where it is secured to said shell by a single bolt 30. With the above described construction, wherein only a single bolt is needed to secure the conductor strapagainst twisting, a proportionally greater area of the statorshell may be utilized for the winding than would be available if fasthe strap at both ends otthe stator shell. The strap 1'? extends slightly beyond the bolt 30 and is bent at rightangles for attachment to another conductor 32 which is connected to the other side of the radio receiving circuit. It will be seen that the two notches 22 serve to locate the rotational axis of the rotor accurately at right angles to the axis of the primary winding.

. erably,

The secondary winding 2 comprises two coils 34 and 35 which are wound upon the spherically curved exterior of the rotor shell at opposite sides of the trunnions and have the usual series connection, as indicated at 36 in Fig. 2. The outermost-turns of the coils are retained in place upon the rotor shell by leans of annular shoulders 38 which are molded upon said shell. lhe coils 3st and 35 are separated and held out of contact with the rotor trunnions by means of bosses 40 (best shown in 5) which project slightly from the spherical surface of the shell and surround the trunnio'ns on the exterior of the rotor shell to prevent the inner turns of said coils from inward lateral displacement. The bosses .40 adequately perform the functions Stated and avoid the use of annular ribs or shoulders such as were heretofore generally employed between the separated coils of the rotor winding for the purpose of retaining the turns of wire in v 'place. A lead 42 (Fig. 2) f om the outer turn of the coil 34 extends inwardly through an aperture in the rotor and is connected with the inner end of the trunnion 12 while a lead 44 from the outer turn of the coil 35 extends similarly through an aperture in the rotor shell and is connected with the inner end of the trunnion 13. The rotor t unnions 12 and 13 extend outwardly beyond the bearing sleeves 1d and 15 and are encircled by coiled springs 37 which bear at their innerends against said sleeves and at their outer ends against nuts 38' and 39 which -are threaded upon said trunnions respectively. The springs 37 yieldingly The slotted end 26 of said oppose the turning of the rotor with suiticient friction to maintain the rotor in adjusted position and they also'serve to insure good electrical contact between the rotor trunnions and the conductors 1d and 17. As shown, the nut 39 is provided with a c0unter-bored recesstlito receive the respective spring 37 and said not is adapted to be turned to vary the compression of the spring. The and 38 upon the othertrunnion be tightened against a shoulder upon the trunnion and secured against. turning by means of solder upon the outer face of the nut. l

To enable the rotor to be turned to vary the amount of the coupling hetween'the primary and the secondary windings, the trun-- nion 12 is extended throughan aperture 42 in the supporting panel 12 and a dial knob 45 is rigidly secured to the trunnion. Pretas shown, the dial knob is provided with an internally screw-threaded bushing 46 which is firmly anchored in the knob and is in threaded engagement with the outer end'of the trunnion 12. The inner end of said bushing bears against the outerend of a bushing or collar 48 that is formed integrally with the nut 39 thus et- 'l'ectively locking the dial ltnob to the rotor trunnion to prevent relative turning of said knob and rotor.

It is sometimes desirable to supply variocouplcrs with primary windings at both sides of the axis of the rotor instead of at one side only. such a coupler being commonly known as a double tube type. If a double tube coupler is to be assembled two stator shells or tubes" are employed these tubes being held together by conductor straps 16" and 17 (Fig. 7) the. strap 16 being 01 the same shape and construction as the strap 16 herebctore referred to. with exception that no offset is formed therein. The strap l7 extends at opposite sides of the rotor bearing carried thereby in the same manner as the strap 16. The conductor straps l6 and 17 are provided with hearingsleeves 14; and 15 for the rotor trunuions and the rotor trunnions are journaled in these bearing sleeves as already described in connection with the preferred Form of the invention. Two stator shells 3 are then assembled with the rotor, these shells being similar in construction as the shell 3 already described. having similar notches tor the reception of the bearing slcevcs tor the rotor trunnions. The two stator shells or tubes 3 are held in assembled relation by means of dowel pins 50 which are inserted in dowel holes that are provided in the abutting edge faces of the tubes. Bolts 51 secure the stator tubes to the conductor straps l7 and bolts 52 extend through the conductor straps l6 and through the stator tubes and are threaded into the lugs and 25 on the panel 12. the curved taces ot' the tubes seating against the correspondingly curved faces of the lugs 93 and Q5.

liy proyiding the two lugs 23 and 25 upon the panel 12 the latter is adapted to support a i'ario-coupler having either a single or double tube stator as may be desired. It a double tube stator is to be assembled upon the panel. the two tubes will be dowclled together as described. It will be, seen that the conductor straps l6 and 16' are the same in construction except that the former has the offset. 27 while the latter hasno such oilsct. Obviously. the conductor straps may be supplied in one form only. i. c. all straps tor assembly with the lugs and 25 may be made straight for assembling a double lube 'stator and the bosses 23 and 25 will properly locate the stator so that the axis ot the rotor will be pependicular to the panel l9. It a single tube stator is to be assembled. the strap 16 may be otlsct at 27 as shown and readily adjusted by bending the same to likewise bring the axis of the ritor to 'ierpendicular position and the slot ted end 26 will accommodate any such adjust-merits.

The invention has been disclosed or i lustrative purposes in an embodiment present preferred. but the scope of the in vention is to be determined from the appended claims rather than from the torcgoing description.

lVhat I claim is:

1. In a dev ce of the described, the combination with the rotor. of a tubular stator having diametrically disposed notch in the edge face at one end thereof. trnn nions carried'by the rotor, her ring siceves adapted to be located in said notches, conductor straps carrying said bearing sleeves and extending transversely across the in-- 6 ner periphery of the stator, and bolts severally extending through each conductor strap at the end remote from the bearing sleeve for securing" the strap to the stator and holding the bearing sleeves in notches.

2. In a device of the class described. the combination with a tubular stator and a rotor adapted to turn on. an axis perpen dicula'r to the axis of the stator. of a supporting panel. :1 lug on said panel having a face curved to conform to the exterior curvature of the stator. trunnions carried by the rotor. bearings for said trunnions. conductors carrying said hearings. a bolt. for securing one of said conductors to the stator and tor securing the stator to said inc. and means for securing the'othcr conductor to the stator.

3. In a device of the class combination with a stator i: trunnions fixed thereto and "escribed the a rotor having bearing sleeves therefor. means for mounting sai t i in said bearing sleeves the latter eea i the edge of said stator comprising; i porting" member -for each trunnion bolted to said stator at a point adjacent the edge of said stator.

4. ln a device of the class described t combination with a stator having recess located at diametrically opposite points 0' an edge thereof. of a rotor having trunnions in said bearing sleeves. the latter engaging within the recesses of said stator comprising a rigid metaihc strap for each bearing sleeve and bolted to said stator .a point adjacent the other edge thereof and adapted to conduct a current to or from said trunnion.

4 6. In a device of the class described, the combination with a stator having recesses ieceted at diametricallyopposite points on an edge thereof, of a rotor having trunii-ions fixed thereto and bearing sleeves therefor, means for mounting said trunnions in said bearingsleeves the latter engaging within the recesses of said stator comprising a rigid metallic strap for each bearing sleeve and bolted to said stator at a point adjacent the other edge thereof and spring actuated means to effect Wiping electrical connections between said fixed strap and movable trunnion whereby said strap is meme:-

adapted to conduct a current to or from said trunnion.

7. In a device of the class described, the combination with a stator of two parts with edges thereof in abutment, of a rotor having trunnions fixed thereto and bearing sleeves therefor, means for mounting said trnnnions in said bearing sleeves and between the abutting edges of said stator parts comprising a rigid strap for each bearing sleeve and bolted to said stator parts adjacent the other edges thereof whereby said parts are retained in assembled relation.

In testimony whereof I have atfixed my signature.

CLARENCE D. TUSKA. 

